de.unihalle.informatik.MiToBo.apps.xylem

Class MathHelper

java.lang.Object

de.unihalle.informatik.MiToBo.apps.xylem.MathHelper

public final class MathHelper
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static double	PI_HALF

Constructor Summary

Constructors

Modifier	Constructor and Description
private	MathHelper()

Method Summary

Modifier and Type	Method and Description
static double	acot(double value) Return the arcus cotangens of value in radian.
static double	angleDiff360(double angleOne, double angleTwo)
static double	calcMean(double[] values) Return the mean value of an array of double.
static double	calcMedian(double[] values) Returns the median value of an array of double.
static double[]	calcMinMax(double[] values) Returns the min and max value.
static double	calcVariance(double[] values) Returns the variance of an array of double.
static double	cot(double value) Return the cotangens of value.
static Point2D.Double	point2DDiff(Point2D.Double pointOne, Point2D.Double pointTwo) Substract two Point2D.Double .
static Point2D.Double	point2DSum(Point2D.Double pointOne, Point2D.Double pointTwo) Sums up two Point2D.Double .
static Point2D.Double	toCartesianAsPoint2D(double angleDegree) Converts an angle in degree to its corresponding in cartesian coordinates.
static double[]	toCartesianAsVector(double angleDegree) Converts an angle in degree to its correspondant in cartesian coordinates.
static double	toPositiveAngle360(double angle) Simple way to convert negative angles to 0-360 degree.
static double[]	unitVector(double[] vector) Return the unit vector of vector.
static double[]	vectorDiff(double[] vecOne, double[] vecTwo) Subtract two vectors.
static double	vectorNorm(double[] vector) Returns the norm of a vector.
static double[]	vectorSum(double[] vecOne, double[] vecTwo) Sums up two vectors.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

PI_HALF

public static final double PI_HALF

See Also:

Constant Field Values

Constructor Detail

MathHelper

private MathHelper()

Method Detail

acot

public static final double acot(double value)

Return the arcus cotangens of value in radian.

This function is implemented as described in "Teubner - Taschenbuch der Mathematik [Bronstein/Samendjajew]".

Parameters:

value - A rational floating point number.

Returns:

The Arcuscotangens of value.

angleDiff360

public static final double angleDiff360(double angleOne,
                                        double angleTwo)

Parameters:

angleOne -

angleTwo -

Returns:

calcMean

public static double calcMean(double[] values)

Return the mean value of an array of double.

Parameters:

values -

Returns:

calcMedian

public static double calcMedian(double[] values)

Returns the median value of an array of double.

Parameters:

values -

Returns:

calcMinMax

public static double[] calcMinMax(double[] values)

Returns the min and max value.

Parameters:

values -

Returns:

calcVariance

public static double calcVariance(double[] values)

Returns the variance of an array of double.

Parameters:

values -

Returns:

cot

public static final double cot(double value)

Return the cotangens of value. In case of 0 the returned value is not a number - the tangens function is not defined for zero -> 1/Infinty is not a number.

Parameters:

value - The argument of the cotangens function.

Returns:

The result of the cotangens function.

point2DDiff

public static final Point2D.Double point2DDiff(Point2D.Double pointOne,
                                               Point2D.Double pointTwo)

Substract two Point2D.Double .

Parameters:

pointOne -

pointTwo -

Returns:

point2DSum

public static final Point2D.Double point2DSum(Point2D.Double pointOne,
                                              Point2D.Double pointTwo)

Sums up two Point2D.Double .

Parameters:

pointOne -

pointTwo -

Returns:

toCartesianAsPoint2D

public static final Point2D.Double toCartesianAsPoint2D(double angleDegree)

Converts an angle in degree to its corresponding in cartesian coordinates.

Parameters:

angleDegree - An angle in degree.

Returns:

A Point2D.Double containing the coordinate in cartesian coordinate system

toCartesianAsVector

public static final double[] toCartesianAsVector(double angleDegree)

Converts an angle in degree to its correspondant in cartesian coordinates.

Parameters:

angleDegree - An angle between 0 and 359 degree.

Returns:

An array with the x and y cartesian coordinate.

toPositiveAngle360

public static final double toPositiveAngle360(double angle)

Simple way to convert negative angles to 0-360 degree.

Parameters:

angle - An angle in the range of [-360,360]

Returns:

vectorDiff

public static double[] vectorDiff(double[] vecOne,
                                  double[] vecTwo)

Subtract two vectors.

Parameters:

vecOne -

vecTwo -

Returns:

vectorNorm

public static double vectorNorm(double[] vector)

Returns the norm of a vector.

Parameters:

vector -

Returns:

unitVector

public static double[] unitVector(double[] vector)

Return the unit vector of vector.

Parameters:

vector -

Returns:

vectorSum

public static final double[] vectorSum(double[] vecOne,
                                       double[] vecTwo)

Sums up two vectors.

Parameters:

vecOne -

vecTwo -

Returns: